Feedback inhibition of dihydrodipicolinate synthase enzymes by L-lysine.

Dihydrodipicolinate synthase (DHDPS) is the first enzyme unique to the lysine biosynthetic pathway and is feedback regulated by L-lysine in plants and some bacteria. The allosteric binding site has been localized by X-ray crystallography and is in agreement with reported mutations of plant DHDPS enzymes, which confer insensitivity to feedback inhibition. Three possible elements of the mechanism of lysine inhibition are discussed.